Sound absorption structure

Abstract

To provide a sound absorption structure applicable to various types of spaces and partitions.SOLUTION: A sound absorption structure 1 includes one plate body 2 and a support body 3. The plate body 1 is a plate-like member having a pair of mutually opposing surfaces 2a and 2b. The support body 3 is a member for supporting the plate body 2 in a direction facing one of a pair of surfaces 2a and 2b. The plate body 2 includes a first vibration resonance system 4 and a second vibration resonance system 5.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a sound absorption structure.

Background Art

[0002] In spaces such as offices, conference rooms, and houses, there are some that require high sound insulation. For this reason, conventionally, in such spaces, a sound absorption structure having a sound absorption function has been provided in partitions of the space such as walls, ceilings, and floors (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Spaces that require sound insulation have various forms, and the portions where sound absorption structures such as space partitions are provided also have various forms. For this reason, for the sound absorption structure, a structure applicable to various forms of spaces and partitions is required, for example, in terms of structure and also in terms of appearance.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a sound absorption structure applicable to various forms of spaces and partitions.

Means for Solving the Problems

[0006] In order to achieve the above object, the sound absorption structure according to the present invention includes a plate body that is a plate-shaped member having a pair of mutually facing surfaces, and a support body that is a member that supports the plate body in a direction facing one of the pair of surfaces, and the plate body includes a first vibration resonance system and a second vibration resonance system.

[0007] In the sound absorption structure according to one aspect of the present invention, the configuration forming the first vibration resonance system is included in the configuration forming the second vibration resonance system.

[0008] In the sound absorption structure according to one aspect of the present invention, the plate body has at least one second resonator that performs membrane vibration, and in the second resonator, there is at least one first resonator that performs membrane vibration. The first resonator forms the first vibration resonance system, and the second resonator forms the second vibration resonance system.

[0009] In the sound absorption structure according to one aspect of the present invention, the first resonator resonates at a frequency higher than that of the second resonator.

[0010] In the sound absorption structure according to one aspect of the present invention, the plate body has a film body that is a film-like member and a frame body that is a member that supports the film body in a direction facing one of the pair of surfaces. The second resonator is formed by at least a part of the film body and the frame body. In the frame body, at least one hole that opens in the direction facing the pair of surfaces is formed in the range of the second resonator, and the portion of the film body facing the hole forms the first resonator.

[0011] In the sound absorption structure according to one aspect of the present invention, a plurality of the holes are formed in the frame body.

[0012] In the sound absorption structure according to one aspect of the present invention, the support body has at least one opening that opens in the direction of the plate body, and the portion of the plate body facing the opening forms the second resonator.

[0013] In the sound absorption structure according to one aspect of the present invention, the support body has a plurality of the openings and is in a lattice shape.

[0014] In the sound absorption structure according to one aspect of the present invention, the support body is closed except for the opening.

Advantages of the Invention

[0015] According to the sound absorption structure of the present invention, it can be applied to various forms of spaces and partitions.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0018] FIG. 1 is a perspective view showing a schematic configuration of a sound absorption structure 1 according to an embodiment of the present invention, FIG. 2 is a view showing the internal structure through a part of the sound absorption structure 1, and FIG. 3 is a cross-sectional view showing a cross-section along line A-A in FIGS. 1 and 2. As shown in FIGS. 1 to 3, the sound absorption structure 1 includes a single plate body 2 and a support 3. The plate body 1 is a plate-shaped member having a pair of mutually facing surfaces 2a and 2b. The support 3 is a member that supports the plate body 2 in a direction facing one of the surfaces 2a and 2b. The plate body 2 has a first vibration resonance system 4 and a second vibration resonance system 5 (see FIGS. 5 and 6 described later). Hereinafter, the configuration of the sound absorption structure 1 will be specifically described. Note that one of the pair of surfaces 2a and 2b of the plate body 2 is the surface 2a.

[0019] As shown in FIGS. 1 to 3, for convenience of explanation, the direction in which the surface 2a, which is one surface of the plate body 2, faces is defined as the sound source side, and the direction in which the surface 2b, which is the other surface of the plate body 2, faces is defined as the fixed side. Also, in the drawings, not all of the plurality of components are labeled, and some of the labels of the plurality of components may be omitted.

[0020] In the sound absorption structure 1, for example, the configuration forming the first vibration resonance system 4 is included in the configuration forming the second vibration resonance system 5. Specifically, for example, the plate body 2 has at least one second resonator 7 that performs membrane vibration, and in the second resonator 7, there is at least one first resonator 6 that performs membrane vibration. The first resonator 6 forms the first vibration resonance system 4, and the second resonator 7 forms the second vibration resonance system 5. That is, the first vibration resonance system 4 is configured as a vibration resonance system including a vibration resonance system in which a resonance phenomenon occurs due to the membrane vibration of the first resonator 6. Also, the second vibration resonance system 5 is configured as a vibration resonance system including a vibration resonance system in which a resonance phenomenon occurs due to the membrane vibration of the second resonator 7. Further, in the sound absorption structure 1, in the plate body 2, the first vibration resonance system 4 overlaps the second vibration resonance system 5. Also, the first resonator 6 is configured to resonate at a higher frequency than the second resonator 7, for example.

[0021] As shown in FIGS. 1 to 3, the plate body 2 has, for example, a membrane body 10 that is a membrane-like member, and a frame body 20 that is a member that supports the membrane body 10 in the direction in which the surface 2a, which is one of the pair of surfaces 2a and 2b, faces. As shown in FIGS. 1 and 3, the surface 2a of the plate body 2 is a surface that faces the outside of the sound absorption structure 1 and faces the sound source side. That is, in the plate body 2, the frame body 20 supports the membrane body 10 toward the sound source side. The membrane body 10 and the frame body 20 are fixed to each other. For example, the membrane body 10 and the frame body 20 are adhered to each other.

[0022] The film body 10 is, for example, a thin film-like member having flexibility, and as shown in FIG. 3, has a pair of mutually facing surfaces 11 and 12. The film body 10 is configured to bend in the direction facing the surfaces 11 and 12, whereby the film body 10 is configured to vibrate. The surface 11 of the film body 10 constitutes the surface 2a in the plate body 2. On the other hand, the surface 12 of the film body 10 is supported by the frame body 20 in the plate body 2. For example, the surface 12a of the film body 10 is fixed to the frame body 20. Specifically, for example, the surface 12 of the film body 10 is adhered to the frame body 20. The film body 10 is made of materials such as paper, soft resin film, felt, and rubber. Note that the material of the film body 10 is not limited to these. Further, the thickness (thickness t1) of the film body 10 is, for example, 0.05 mm or more and 1.0 mm or less. Note that the thickness t1 of the film body 10 is not limited to this. As shown in FIG. 3, the thickness t1 of the film body 10 is the distance between the surface 11 and the surface 12.

[0023] The frame body 20 is a member having flexibility, and as shown in FIG. 2, has a plurality of holes 21. Note that in FIG. 2, the film body 10 is shown as being transparent. Further, the frame body 20 extends along a plane and has a thin plate-like or film-like appearance. The frame body 20 forms a pair of mutually facing surfaces 22 and 23 as shown in FIG. 3. The surface 22 of the frame body 20 supports the film body 10 in the plate body 2. That is, the surface 22 of the frame body 20 is in contact with the surface 12 of the film body 10, and the film body 10 is fixed to the surface 22 of the frame body 20. On the other hand, the surface 23 of the frame body 20 constitutes the surface 2b in the plate body 2. The holes 21 are holes that open toward the sound source side and the fixed side as shown in FIG. 3, and penetrate between the surface 22 and the surface 23.

[0024] As shown in FIGS. 2 and 3 for example, the frame body 20 has a plurality of holes 21. In the frame body 20, the plurality of holes 21 are formed like a mesh. When viewed toward the sound source side or the fixed side, the shape of the plurality of holes 21 is rectangular or substantially rectangular as shown in FIG. 2 for example. Also, as shown in FIG. 2 for example, the plurality of holes 21 are aligned and arranged in the longitudinal direction (the direction of arrow a in FIG. 2), which is one direction, and the lateral direction (the direction of arrow b in FIG. 2), which is a direction orthogonal to the longitudinal direction. That is, in the frame body 20, the plurality of holes 21 are arranged along the surfaces 22 and 23 in a matrix shape for example. For this reason, the frame body 20 has portions extending in the direction in which the plurality of holes 21 are arranged. For example, as shown in FIG. 2, there are a plurality of vertical frame portions 24, which are portions extending in the longitudinal direction, and a plurality of horizontal frame portions 25, which are portions extending in the lateral direction. Each vertical frame portion 24 intersects a plurality of horizontal frame portions 25, and each horizontal frame portion 25 intersects a plurality of vertical frame portions 24. Specifically, for example, each vertical frame portion 24 is orthogonal or substantially orthogonal to a plurality of horizontal frame portions 25, and each horizontal frame portion 25 is orthogonal or substantially orthogonal to a plurality of vertical frame portions 24.

[0025] In the frame body 20, the vertical frame portions 24 located at the respective lateral ends and the horizontal frame portions 25 located at the respective longitudinal ends may form the outer edge of the frame body 20 as shown in FIG. 2 for example. In this case, as shown in FIG. 2, the vertical frame portion 24 and the horizontal frame portion 25 forming the outer edge of the frame body 20 do not intersect, and the horizontal frame portion 25 extends up to the vertical frame portion 24 forming the outer edge of the frame body 20. Similarly, as shown in FIG. 2, the horizontal frame portion 25 and the vertical frame portion 24 forming the outer edge of the frame body 20 do not intersect, and the vertical frame portion 24 extends up to the horizontal frame portion 25 forming the outer edge of the frame body 20. Also, the shape of the holes 21 is not limited to a rectangle, and may be other polygons such as a hexagon or other shapes such as a circle. When the shape of the holes 21 is a rectangle or a hexagon, the aperture ratio of the frame body 20 can be increased. The aperture ratio of the frame body 10 is the ratio of the total opening area, which is the sum of the opening areas of all the through holes 41, to the area of the surface 22 or the surface 23 of the frame body 10. Also, the arrangement of the plurality of holes 21 is not limited to a matrix shape, and may be other modes.

[0026] As described above, the frame body 20 is a flexible member and is formed from a flexible material. The material of the frame body 20 is, for example, resin, wood, metal, etc. Specifically, the material of the frame body 20 is, for example, hard resin, soft resin, bamboo, etc. Note that the material of the frame body 20 is not limited to these materials. The frame body 20 has a plurality of vertical frame portions 24 and a plurality of horizontal frame portions 25 connected to each other, presenting a thin plate-like or film-like appearance as described above, and the frame body 20 is configured to bend in the direction facing the surfaces 22 and 23. Thereby, the frame body 20 is configured to vibrate like a membrane. For example, a punching board is used for the frame body 20.

[0027] The thickness (t2) of the frame body 20 is, for example, 0.5 mm or more and 3 mm or less. As shown in FIG. 3, the thickness t2 of the frame body 20 is the distance between the surface 22 and the surface 23. Also, the size (w1) of the hole 21 is, for example, 10 mm or more and 100 mm or less. The size w1 of the hole 21 is the width in the direction along the surfaces 21 and 22 of the hole 21, and is, for example, the maximum or minimum width. For example, as shown in FIG. 3, the size w1 of the hole 21 is the length of one side of the hole 21. In the illustrated example, the hole 21 is square, and the size in the vertical direction (arrow a direction) and the size in the horizontal direction (arrow b direction) of the hole 21 are equal, being the size w1. When the hole 21 is rectangular, either the length of one side in the vertical direction or the length of one side in the horizontal direction of the hole 21 is w1. Note that the thickness t2 of the frame body 20 is not limited to the above value. Also, the size w1 of the hole 21 is not limited to the above value.

[0028] As shown in FIG. 1, the film body 10 and the frame body 20 face each other, and the film body 10 is fixed to the frame body 20. Specifically, for example, as shown in FIG. 3, the surface 12 of the film body 10 and the surface 22 of the frame body 20 are adhered to each other, and the film body 10 is pasted on the surface 22 of the frame body 20. Further, the sizes of the surfaces 11 and 12 of the film body 10 are, for example, the same as or substantially the same as the sizes of the surfaces 22 and 23 of the frame body 20. That is, the film body 10 is adhered to the surface 22 of each of the plurality of vertical frame portions 24 and the plurality of horizontal frame portions 25 of the frame body 20, spreads on the surface 22 of the frame body 20, is stretched on the vertical frame portion 24 and the horizontal frame portion 25 surrounding each hole 21, and spreads facing all the holes 21.

[0029] In this way, in the plate body 2, the film body 10 spreads over the entire surface 22 of the frame body 20, and a film piece 13 is formed by the film body 10 on the sound source side of each hole 21 (see FIG. 1). Note that the film piece 13 is a portion of the film body 10 facing each hole 21. In this way, in the plate body 2, a film piece 13 is formed corresponding to each hole 21 of the frame body 20, and each film piece 13 vibrates in the film vibration manner by vibrating on the sound source side and the fixed side. Note that in FIG. 1, only some of the film pieces 13 are shown.

[0030] As described above, the flexible frame body 20 vibrates in the film vibration manner on the sound source side and the fixed side. The flexible film body 10 is stretched on the surface 22 facing the direction of the film vibration of the frame body 20, and the plate body 2 integrally vibrates in the direction facing the surfaces 2a and 2b to perform film vibration. Further, the plate body 2 vibrates partially or entirely in the film vibration manner.

[0031] As described above, the whole or part of the plate body 2 vibrates in the film vibration manner, and each film piece 13 of the film body 10 vibrates in the film vibration manner independently of the film vibration of the plate body 2. In this way, the plate body 2 includes a second vibration system 5 in which the plate body 2 vibrates in the film vibration manner and a first vibration system 4 in which each film piece 13 of the film body 10 vibrates in the film vibration manner (see FIGS. 5 and 6 described later).

[0032] As shown in FIG. 3, the support 3 supports the surface 2b of the plate body 2. As shown in FIGS. 2 and 3 for example, the support 3 has at least one opening 31 that opens in the direction of the plate body 2. Each opening 31 faces the surface 2b of the plate body 2, and the portion of the plate body 2 facing each opening 31 forms the second resonator 7 (see FIG. 1). As described above, the plate body 2 vibrates in a membrane-like manner. The plate body 2 is supported by the support 3, and the plate piece 8 (see FIG. 1), which is the portion of the plate body 2 facing each opening 31 of the support 3, vibrates on the sound source side and the fixed side and vibrates in a membrane-like manner. Thus, each plate piece 8 of the plate body 2 forms the second vibration system 5 that vibrates in a membrane-like manner.

[0033] FIG. 4 is a perspective view showing a schematic configuration of the support 3. As an example, the support 3 has a plurality of openings 31 and is in a lattice shape. Specifically, for example, as shown in FIGS. 2 and 4, the opening 31 is rectangular or substantially rectangular, and in the support 3, the plurality of openings 31 are aligned and arranged in the vertical direction (arrow a direction) and the horizontal direction (arrow b direction). That is, in the support 3, the plurality of openings 31 are arranged in a matrix along the plate body 2.

[0034] Specifically, for example, as shown in FIGS. 2 to 4, the support 3 has at least one each of lattice bodies 32, 33, 34 configured to form a plurality of spaces 35 each having an opening 31. Specifically, the support 3 has a peripheral lattice body 32 surrounding a space that houses the plurality of spaces 35, and vertical lattice bodies 33 and horizontal lattice bodies 34 that divide the space surrounded by the peripheral lattice body 32 into the plurality of spaces 35. The peripheral lattice body 32, the vertical lattice bodies 33, and the horizontal lattice bodies 34 are members having a height (height h1) in the direction in which the surfaces 2a, 2b face, and each has the same or substantially the same height h1. Further, as shown in FIG. 2, the peripheral lattice body 32 forms the outer edge of the support 3 and extends annularly so as to surround the space, and for example, extends annularly in a rectangular or substantially rectangular shape so as to surround a rectangular or substantially rectangular space. That is, as shown in FIG. 4, the peripheral lattice body 32 has vertical pieces 32a, 32b that are portions extending in the vertical direction and horizontal pieces 32c, 32d that are portions extending in the horizontal direction. The vertical piece 32a and the vertical piece 32b face each other, and the horizontal piece 32c and the horizontal piece 32d face each other. The horizontal piece 32c extends between one ends of the vertical pieces 32a, 32b, and the horizontal piece 32d extends between the other ends of the vertical pieces 32a, 32b. The area of the peripheral lattice body 32 and the space surrounded by the peripheral lattice body 32 as viewed from the sound source side or the fixed side is, for example, the same as or substantially the same as the area of the surfaces 2a, 2b of the plate body 2.

[0035] The vertical lattice body 33 and the horizontal lattice body 34 extend into the space surrounded by the peripheral lattice body 32 and intersect each other. The vertical lattice body 33 and the horizontal lattice body 34 partition the space surrounded by the peripheral lattice body 32, and define a plurality of spaces 35 within the space surrounded by the peripheral lattice body 32. Each of the plurality of spaces 35 has an opening 31 on the side of the plate body 10. The vertical lattice body 33 and the horizontal lattice body 34 extend linearly, for example. In the support body 3, the vertical lattice body 33 extends parallel or substantially parallel to the vertical pieces 32a, 32b of the peripheral lattice body 32, and the horizontal lattice piece 34 extends parallel or substantially parallel to the horizontal pieces 32c, 32d of the peripheral lattice piece 32. The vertical lattice body 33 and the horizontal lattice body 34 are orthogonal or substantially orthogonal to each other, for example. Thus, the vertical lattice body 33 and the horizontal lattice body 34 form a plurality of rectangular or substantially rectangular openings 31 at the end face 3a on the plate body 2 side of the support body 3. Further, the vertical lattice body 33 and the horizontal lattice body 34 form a plurality of cuboid or substantially cuboid spaces 35 in the space surrounded by the peripheral lattice body 32. The shape of the space 35 when viewed from the space 35 toward the fixed side is the same as or substantially the same as the shape of the opening 31, for example.

[0036] As an example, as shown in FIGS. 2 and 4, the support body 3 has one vertical lattice body 33 and a plurality of horizontal lattice bodies 34. The number of vertical lattice bodies 33 of the support body 3 is not limited to this, and may be plural. Similarly, the number of horizontal lattice bodies 34 of the support body 3 is not limited to this, and may be one or other plural.

[0037] Note that the shape of the opening 31 of the support body 3 is not limited to a rectangle, and may be other polygons such as a hexagon or other shapes such as a circle. In this case, the lattice bodies 32, 33, 34 are formed in a form corresponding to the shape of the opening 31. Further, the arrangement of the plurality of openings 31 in the support body 3 is not limited to the above, and other arrangements may be possible.

[0038] Also, as shown in FIGS. 2 to 4, the support 3 is closed except for the opening 31. Specifically, for example, as shown in FIG. 2, the support 3 has a bottom 36 which is a portion covering the opening on the opposite side of the opening 31 of each space 35. The bottom 36 is, for example, a plate-like portion, and the ends on the opposite side of the opening 31 of the peripheral lattice body 32, the vertical lattice body 33, and the horizontal lattice body 34 are connected. The peripheral lattice body 32, the vertical lattice body 33, and the horizontal lattice body 34 are erected on the bottom 36. Thus, each space 35 is open only at the opening 31.

[0039] The support 3 is formed of, for example, a hard material. The hard material is, for example, a hard resin, and specifically, for example, rigid vinyl chloride, polyethylene terephthalate (PET), polycarbonate (PC), etc. Also, the support 3 may be formed of, for example, a soft material. The soft material is, for example, a soft resin, a foamed resin, cardboard, etc. The foamed resin includes, for example, a polyethylene resin, a foamed propylene resin, etc. The soft material can be used, for example, according to the frequency band for which sound absorption is desired. The support 3 is integrally formed from, for example, the same material. That is, the peripheral lattice body 32, the vertical lattice body 33, the horizontal lattice body 34, and the bottom 36 of the support 3 are each part of the support 3 formed from the same material and are connected to each other. Note that any one or all of the peripheral lattice body 32, the vertical lattice body 33, the horizontal lattice body 34, and the bottom 36 may be formed separately from each other and then connected by an adhesive or the like.

[0040] The thickness t3 (see FIG. 4) of the peripheral grid body 32, the vertical grid body 33, the horizontal grid body 34, and the bottom portion 36 is, for example, 1.0 mm or more and 5.0 mm or less. Note that the thickness t3 of the peripheral grid body 32, the vertical grid body 33, and the horizontal grid body 34 is the width in the horizontal or vertical direction and is the width in the direction along the direction in which the bottom portion 36 spreads. Further, the height h1 of the support body 3 is, for example, 10 mm or more and 100 mm or less. The height h1 of the support body 3 is the width of the support body 3 in the direction in which the peripheral grid body 32, the vertical grid body 33, and the horizontal grid body 34 stand with respect to the bottom portion 36. The heights of the peripheral grid body 32, the vertical grid body 33, and the horizontal grid body 34 are the height h1 of the support body 3. Further, the size w2 of the opening portion 31 is, for example, 2 times or more and 20 times or less the size of the hole 21 of the frame body 20. Note that the size w2 of the opening portion 31 is the width in the direction along the bottom portion 36 of the opening portion 31 and is, for example, the maximum or minimum width. For example, as shown in FIG. 4, the size w2 of the opening portion 31 is the length of one side of the opening portion 31. In the illustrated example, the opening portion 31 is rectangular, one side in the horizontal direction (arrow b direction) of the opening portion 31 is longer than one side in the vertical direction (arrow a direction), and the length of one side in the horizontal direction of the opening portion 31 is w2. When the opening portion 31 is square, the vertical size and the horizontal size of the opening portion 31 are equal and are the size w2. Note that the thickness t3 of the support body 3 is not limited to the above value. Further, the height h1 of the support body 3 is not limited to the above value. Further, the size w2 of the opening portion 31 of the support body 3 is not limited to the above value.

[0041] As shown in FIGS. 1 to 3, the support body 3 supports the surface 2b of the plate body 2. For example, the end portion 3a on the opening portion 31 side of the support portion 3 is connected to the surface 2b of the plate body 2 and supports the plate body 2. Specifically, the end portion 32e of the peripheral grid body 32, the end portion 33a of the vertical grid body 33, and the end portion 34a of the horizontal grid body 34 are connected to the surface 2b of the plate body 2. For example, the support portion 3 and the plate body 2 are fixed to each other and connected by adhesion.

[0042] As shown in FIGS. 2 and 3, the plate body 2 is placed on the end face 3a on the open portion 31 side of the support body 3 on the surface 2b side. For example, the end portion 33a of the vertical grid body 33 of the support body 3 is connected to the vertical frame portion 24 of the corresponding frame body 20, and the end portion 34a of the horizontal grid body 34 of the support body 3 is connected to the horizontal frame portion 25 of the corresponding frame body 20. The end portions 32e of the peripheral grid body 32 of the support body 3 are respectively connected to the vertical frame portion 24 and the horizontal frame portion 25 that form the outer peripheral edge of the corresponding frame body 20. The end portion 32e of the peripheral grid body 32 is connected to, for example, the vertical frame portion 24 and the horizontal frame portion 25 that form the outer edge of the frame body 20.

[0043] The sound absorption structure 1 is formed by connecting a plate body 2 formed from a film body 10 and a frame body 20 and a support body 3. As shown in FIGS. 1 to 3, the plate body 2 is fixed to the end face 3a of the support body 3, and the plate body 2 is stretched over the peripheral grid body 32, the vertical grid body 33, and the horizontal grid body 34, or the vertical grid body 33 and the horizontal grid body 34 that surround each space 35 of the support body 3, and the plate body 2 spreads over all the open portions 31. In this way, a plate piece 8 that is a part of the plate body 2 faces the open portion 31 of the support body 3 (see FIG. 1), and the plate piece 8 is stretched over each open portion 31. Note that the plate piece 8 is a portion of the plate body 2 that faces the open portion 31 of each space 35 in the sound absorption structure 1 and is a portion of the plate body 2 that covers each open portion 31. As described above, the plate body 2 has flexibility to perform film vibration, and the plate piece 8 also performs film vibration. Further, as shown in FIG. 1, each plate piece 8 has holes 21 of a plurality of frame bodies 20, and a film piece 13 is stretched over each hole 21. The film piece 13 performs film vibration.

[0044] In this way, in the sound absorption structure 1, the plate piece 8 attached to the open portion 31 of each space 35 formed in the support body 3 forms the second resonator 7. That is, a part of the plate piece 8 of the plate body 2 in which the film body 10 and the frame body 20 are integrated resonates at a specific frequency and acts as an inertial mass at that time. Further, in the sound absorption structure 1, the space 35 in which each plate piece 8 is stretched forms the second resonator 7 together with the plate piece 8. That is, the air in the space 35 acts as an air spring with respect to the plate piece 8 that performs film vibration.

[0045] Thus, in the sound absorption structure 1, each plate piece 8 and the space 35 corresponding to this plate piece 8 form the second resonator 7, creating a spring-mass resonance system that resonates at a specific frequency. A plurality of plate pieces 8 are formed in the sound absorption structure 1, and the sound absorption structure 1 has a plurality of second resonators 7.

[0046] Also, in the sound absorption structure 1, in each plate piece 8 of the sound absorption structure 1, the film pieces 13 attached to the respective holes 21 formed in the frame body 20 form the first resonator 6. That is, some of the film pieces 13 of the film body 10 resonate at a specific frequency and act as inertial masses at that time. Further, in the sound absorption structure 1, the holes 21 in which the respective film pieces 13 are stretched, together with the film pieces 13, form the first resonator 6. That is, the air in the holes 21 acts as an air spring with respect to the vibrating film pieces 13.

[0047] Thus, in the sound absorption structure 1, each film piece 13 and the hole 21 corresponding to this film piece 13 form the first resonator 6, creating a spring-mass resonance system that resonates at a specific frequency. A plurality of film pieces 13 are formed in each plate piece 8 of the sound absorption structure 1, and each plate piece 8, that is, each second resonator 7, has a plurality of first resonators 6.

[0048] As described above, in the sound absorption structure 1, the first resonator 6 constitutes the first vibration resonance system 4, and the second resonator 7 constitutes the second vibration resonance system 5. Further, the film pieces 13 of the film body 10 included in the plate pieces 8 that constitute the second resonator 7 constitute the first resonator 6. In the sound absorption structure 1, each plate piece 8 and the corresponding space 35 constitute the first vibration resonance system 4 and the second vibration resonance system 5, which are two different vibration resonance systems. Also, in the sound absorption structure 1, a plurality of first resonators 6 constitute the first vibration resonance system 4, and a plurality of second resonators 7 constitute the second vibration resonance system 5. Thus, the sound absorption structure 1 has a three-layer structure of the film body 10, the frame body 20, and the support body 3, and has two types of film vibration systems.

[0049] The size w1 of the hole 21 in the frame body 20 is smaller than the size w2 of the opening 31 of the support body 3, and the mass of the first resonator 6 is smaller than the mass of the second resonator 7. For this reason, the film mass of the first vibration resonator 6 is small and the film elasticity is high, and the first resonator 6 resonates at a higher frequency than the second resonator 7. Therefore, the first vibration resonance system 4 resonates at a higher frequency than the second vibration resonance system 5.

[0050] On the other hand, the film piece 8 has a part of the film body 10 and a part of the frame body 20. Also, the size w2 of the opening 31 is larger than the size w1 of the hole 21, and the mass of the second resonator 7 is larger than the mass of the first resonator 6. Further, the opening 31 is large, the second resonator 7 is soft, and the film elasticity is low. For this reason, the second resonator 7 resonates at a low frequency. Therefore, the second vibration resonance system 5 resonates at a low frequency.

[0051] The resonance frequencies of the first resonator 6 and the second resonator 7 can be set to arbitrary frequencies using, for example, the elastic modulus and specific gravity of the film body 10 and the frame body 20, the size w1 of the hole 21 in the frame body 20, the size w2 of the opening 31 of the support body 3, the height h1 of the support body 3, etc. as parameters.

[0052] FIG. 5 is a schematic diagram showing the first vibration resonance system 4, and FIG. 6 is a schematic diagram showing the second vibration resonance system 5. In FIG. 5, the magnitude of the amplitude at each of the first resonators 6 is shown. In FIG. 5, the darker the color, the larger the amplitude. Similarly, in FIG. 6, the magnitude of the amplitude at each of the second resonators 7 is shown. In FIG. 6, the darker the color, the larger the amplitude.

[0053] As described above, the sound absorption structure 1 has overlapping first and second vibration resonance systems 4 and 5, which are two different vibration resonance systems, and is configured by overlapping two different sound absorbers. Therefore, the sound absorption structure 1 can absorb more sound in a small space. That is, the sound absorption structure 1 can exhibit a high sound absorption effect in a small space. Thus, the space required for installing the sound absorption structure 1 is small, and the sound absorption structure 1 can be applied to various forms of spaces and partitions. Also, since the sound absorption structure 1 exhibits a high sound absorption effect, it can exhibit a high sound absorption effect in various forms of spaces and partitions.

[0054] In addition, the surface (surface 2a) on the sound source side of the sound absorption structure 1 can be made into a smooth surface without unevenness. Therefore, the sound absorption structure 1 can also be easily applied to various forms of spaces and partitions in terms of the appearance surface.

[0055] Also, by making the film body 10, the frame body 20, and the support body 3 of the sound absorption structure 1 from a transparent resin, the sound absorption structure 1 can be made transparent. Therefore, the sound absorption structure 1 can be suitably used for spaces where transparency and daylighting are to be ensured for partitions such as walls, ceilings, and floors, such as a space partitioned by a glass partition or a space having a transparent daylighting window on the ceiling.

[0056] Also, according to the sound absorption structure 1, by adjusting the mass and rigidity of the film body 10, the frame body 20, and the support body 3, a lightweight sound absorption structure can be enabled.

[0057] As described above, according to the sound absorption structure 1 according to the embodiment of the present invention, it can be applied to various forms of spaces and partitions.

[0058] Although the present invention has been described through the above embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various changes or improvements can be made to the above embodiments. It is clear from the description of the claims that forms with such changes or improvements can also be included in the technical scope of the present invention.

[0059] The embodiments described above are for facilitating the understanding of the present invention and are not for limiting and interpreting the present invention. Also, the above embodiments do not limit the objects to which the present invention is applied, and the present invention can include any object as its application target. Each component included in the above embodiments, as well as its arrangement, material, conditions, shape, size, etc. are not limited to those exemplified and can be changed as appropriate. For example, the present invention includes differences that occur in the implementation of manufacturing tolerances and the like. Also, within a technically non - conflicting range, components shown in different embodiments can be partially substituted or combined with each other. Further, each configuration can be selectively combined as appropriate so as to achieve at least part of the above - mentioned problems and effects.

[0060] For example, the number of the first resonators 6 is not limited to the number described above. Also, the number of the second resonators 7 is not limited to the number described above. For example, in each of the second resonators 7, only one first resonator 6 may be provided. Also, the sound - absorbing structure 1 may have only one second resonator 7.

Explanation of Reference Numerals

[0061] 1 Sound absorption structure, 2 Plate body, 2a, 2b Surfaces, 3 Support body, 3a End face, 4 First vibration resonance system, 5 Second vibration resonance system, 6 First resonator, 7 Second resonator, 8 Plate piece, 10 Film body, 11, 12 Surfaces, 13 Film piece, 20 Frame body, 21 Hole, 22, 23 Surfaces, 24 Vertical frame part, 25 Horizontal frame part, 31 Opening part, 32 Peripheral lattice body, 32a, 32b Vertical pieces, 32c, 32d Horizontal pieces, 32e End part, 33 Vertical lattice body, 33a End part, 34 Horizontal lattice body, 34a End part, 35 Space, 36 Bottom, h1 Height, t1, t2, t3 Thickness, w1, w2 Size

Claims

1. A plate body which is a plate-shaped member having a pair of mutually facing surfaces, A support body which is a member that supports the plate body in a direction of one of the pair of surfaces, and comprises: The plate body includes a first vibration resonance system and a second vibration resonance system, A sound absorption structure.

2. The configuration forming the first vibration resonance system is included in the configuration forming the second vibration resonance system, The sound absorption structure according to Claim 1.

3. The plate body has at least one second resonator that performs membrane vibration, and in the second resonator, has at least one first resonator that performs membrane vibration, The first resonator forms the first vibration resonance system, The second resonator forms the second vibration resonance system, The sound absorption structure according to Claim 2.

4. The first resonator resonates at a frequency higher than that of the second resonator, The sound absorption structure according to Claim 3.

5. The plate body has a membrane body which is a membranous member and a frame body which is a member that supports the membrane body in a direction of one of the pair of surfaces, The second resonator is formed by at least a part of the membrane body and the frame body, At least one hole that opens in a direction of the pair of surfaces is formed in the frame body within a range of the second resonator, A portion of the membrane body facing the hole forms the first resonator, The sound absorption structure according to Claim 3.

6. A plurality of the holes are formed in the frame body, The sound absorption structure according to Claim 5.

7. The support body has at least one opening portion that opens in a direction of the plate body, A portion of the plate body facing the opening portion forms the second resonator, The sound absorption structure according to Claim 3.

8. The support body has a plurality of the opening portions and is in a lattice shape, The sound absorption structure according to Claim 7.

9. The support body is closed except for the opening portion, The sound absorption structure according to Claim 7.

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